The connectors are used in various applications, for example, electrical connectors are used for connecting electrical elements used for continuous transmission of power. Generally, the connector assembly includes a male connector sub-assembly and a female connector sub-assembly. The male connector sub-assembly includes a conductive male pin contact at the front and the base portion for electrical wire termination or connection with an insulated cover body assembled over the conductive male pin contact. The female connector sub-assembly includes a conductive female sleeve contact at the front and the base portion for electrical wire termination or connection with an insulated cover body assembled on the conductive female sleeve contact.
The conductive female sleeve contact of the female connector sub-assembly receives the conductive male pin contact of the male connector sub-assembly for configuring the connector assembly. The male and female connector sub-assemblies are connected to each other via engagement between the conductive male pin contact and the conductive female sleeve contact to configure the connector assembly used for continuous transmission of power in the most extreme conditions. Typical applications include use as a connector assembly for transmission of power from generator sets to switchgear or SCR (silicon-controlled rectifiers) controls, from a control house to the traction motors, mud pumps, draw works, rotary tables, cement pumps and top drives. More specifically, the electrical connector assembly is used for connecting an electrical cable to a fixed mating connector. Certain electrical connector assemblies are configured specifically to cater to the drilling rig industry. These connector assemblies are configured for applications where the connector assemblies are required to operate in the most extreme service conditions and are subjected to up to 1,000 Volts AC or DC voltage and up to 1,135 Amps of continuous power.
The field assembly and the installation of many inland drilling rigs have been using single pole electrical connector assemblies that can be prepared in the field. These connector assemblies take different forms, including pin and collet type connector assemblies or plug and receptacle type connector assemblies. All of these types of connector assemblies, particularly, the plug and receptacle type connector assemblies require a desired fit between elements of a plug or a male connector sub-assembly and a receptacle or a female connector sub-assembly to ensure minimal resistance to the high current loads.
However, due to the extreme service conditions to which the connector assembly is subjected to, it is difficult to maintain a desired fit between the elements of the male and female connector sub-assemblies of the connector assembly. Particularly, the connector assemblies are subjected to most extreme service conditions and have to withstand vibrations, shocks and wear and tear. Generally, the elements of the male and female connector sub-assemblies, particularly, the engaging conductive male pin contact and conductive female sleeve contact wear out and fail to maintain the necessary tight fit between the male and female connector sub-assemblies and because of improper contact between the male and female connector sub-assemblies, the connection assembly fails to efficiently transmit power there-though due to high resistance to the high current loads and there are chances of power leakage and damage to the connector assembly.
To achieve the desired fit between the conductive male pin contact and the conductive female sleeve contact of the respective male and female connector assemblies of the connector assembly, the use of a self-adjustable male connector assembly has been suggested in the prior art, wherein the conductive male pin contact of the male connector assembly has a split pin configuration that facilitates in adjusting the conductive male pin's external diameter. In case of the split pin configuration of the conductive male pin contact, the conductive male pin contact is cut into two halves by a slot cut along the length of the conductive male pin contact. A Belleville washer and a fixing stud mechanism are generally used within the slot to make small adjustments in the external diameter of the conductive male pin contact. A fixing stud is driven into the conductive male pin contact that exerts a force against the Belleville washer. By increasing this force, the two sides of the conductive male pin contact are separated and selectively urged away from each other resulting in a slight increase in the diameter of the conductive male pin contact to ensure the necessary fit thereof with the female sleeve contact of the female connector sub-assembly. The female sleeve contact of the female connector sub-assembly has a uniform internal diameter along the conductive length thereof for receiving the conductive male pin contact therein.
However, such a configuration of connector assembly wherein diameter of the conductive male pin contact can be adjusted has certain drawbacks associated therewith. More specifically, the variable diameter conductive male pin contact of the male connector sub-assembly of the connector assembly is field adjustable, however, adjusting the diameter of the conductive male pin contact in the field is not desirable as field operators often lack the knowledge and expertise to make the fine adjustments required for such connections. Accordingly, there is a need for a connector assembly that provides selective access to the adjusting mechanism of the conductive male pin connector of the male connector sub-assembly and may only permit factory adjustment of the male and female connector sub-assemblies for achieving the necessary fit between the conductive male pin contact and the conductive female sleeve contact of the respective male and female connector assemblies by skilled and trained professionals only and restrains field adjustment of the conductive male pin contact and the conductive female sleeve contact of the respective male and female connector assemblies.
The prior art also discloses a connector assembly that permits factory adjustment of the connector sub-assemblies for achieving the necessary fit between engaging elements of the connector sub-assemblies, for example, U.S. Pat. No. 7,442,096 discloses a connector assembly having a variable diameter conductive male pin contact that permits factory adjustment only. More specifically, the conductive male pin contact of the connector assembly includes an adjustment port with threaded hole configured on one side of the tip of the conductive male pin contact, wherein the port receives an adjustment screw that urges a Belleville washer arrangement disposed within a slit axially configured on the conductive male pin contact for adjusting the diameter of the conductive male pin contact by adjusting spacing between the portions of the conductive male pin contact separated by the slot. The access to the adjustment screw is selective so that the adjustment of the conductive male pin's diameter can be performed by skilled and trained professionals only. More specifically, the male sub-assembly includes an adjustment port safety cap for providing selective access to the adjustment screw for permitting factory adjustment of the conductive male pin's diameter only. Such a configuration of the male connector sub-assembly facilitates adjustment of the conductive male connector pin's diameter prior to installation of the safety cap. However, such configuration of the adjustment mechanism for adjusting conductive the male connector pin's diameter is ineffective because of limited contact between the Belleville of the Belleville washer arrangement and the portions of the conductive male connector pin separated by the slot. Further, the gap between the portions of the conductive male connector pin is increased to increase the diameter of the conductive male connector pin by decompressing the Belleville washer arrangement and is not controlled. Further, with such configuration the adjusting of diameter of the conductive male connector pin is not uniform along the contact length.
However, none of the prior art provides any provision for adjusting the dimension of the conductive female sleeve contact of the female connector sub-assembly for ensuring a tight fit between the male and female connector sub-assemblies. More specifically, the contact surface of the conductive female sleeve contact wears during service after assembly and may cause a poor fit between the conductive male pin contact and the conductive female sleeve contact of the respective male and female connector assemblies. In case of a conventional connector assembly, the contact force between the contact surface of the conductive male pin contact and the conductive female sleeve contact of the respective male and female connector assemblies is not uniform along the length of the connector assembly, particularly, the contact force varies from a maximum at the tip of the conductive male pin contact to a minimum at the tip of the conductive female sleeve contact and is detrimental for maintaining proper contact between the engaging elements of the male and female connector assemblies that results in inefficient power transmission.
Accordingly, there is a need for a connector assembly that has provision for adjusting the internal diameter of the conductive female sleeve contact of the female connector sub-assembly along with provision for adjusting the external diameter of the conductive male connector pin of the male connector sub-assembly for ensuring a tight fit between the male and female connector sub-assemblies. Further, there is a need for a connector assembly that ensures uniform contact force between the contact surfaces of the conductive male connector pin and conductive female sleeve of the respective male and female connector assemblies along the length of the connector assembly. Further, there is a need for a connector assembly having such a configuration that the access to the adjustment mechanism for adjusting the internal and external diameters of the conductive male connector pin and conductive female sleeve of the respective male and female connector sub-assemblies is selective so as to permit factory adjustment of the engaging elements of the male and female connector sub-assemblies by skilled and trained professionals only.